218908851 has 16 divisors (see below), whose sum is σ = 334481664. Its totient is φ = 124750944.

The previous prime is 218908831. The next prime is 218908883. The reversal of 218908851 is 158809812.

It is not a de Polignac number, because 218908851 - 2⁵ = 218908819 is a prime.

It is a super-2 number, since 2×218908851² = 95842170092280402, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (218908831) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6141 + ... + 21806.

It is an arithmetic number, because the mean of its divisors is an integer number (20905104).

Almost surely, 2^218908851 is an apocalyptic number.

218908851 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

218908851 is a deficient number, since it is larger than the sum of its proper divisors (115572813).

218908851 is a wasteful number, since it uses less digits than its factorization.

218908851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28330.

The product of its (nonzero) digits is 46080, while the sum is 42.

The square root of 218908851 is about 14795.5686271262. The cubic root of 218908851 is about 602.6813797098.

The spelling of 218908851 in words is "two hundred eighteen million, nine hundred eight thousand, eight hundred fifty-one".